Chat: Dr David Evans

60 Minutes presents a live interview with mathematician and scientist, Dr David Evans. David is here to talk to us tonight about global warming.

Interviewer: Dr Evans, thank you for joining us tonight.

Dr David Evans: Thanks for listening to me, the sceptical case has been ignored by the press till now and I think you'll find it very strong. People are finally coming to terms with it now.

BruceV asks: David, we are about to have a terrible new tax imposed on us, surely if this government is interested in the truth they will listen to you? Thank you for speaking out and for having the courage to speak the truth.

Dr David Evans: Thank you, the reason I spoke out now is because it seemed the situation got beyond stupid and our decision makers need to be reminded than the science has changed since the last 10 years. Unfortunately, the public are also unaware of the science in the last few years and I think if they were aware there would be a public outcry that these taxes do not go ahead.

finallysomesense asks: Is the IPCC still a relevant body, or have the political considerations become such that the science is lost in the fallout for these 'scientists'?

Dr David Evans: The IPCC is a UN bureaucracy. Less than half of the 2500 involved are scientists, most are bureaucrats. The IPCC is reluctant to consider causes of global warming other than human ones. The fact that temperatures haven't risen since 2001 means that their politics are becoming untenable.

Aussie asks: Shouldn't the government be paying incentives to companies who produce a cleaner environment rather than charging them and allowing them to keep polluting it, anyway you put it we the taxpayer still pay.

Dr David Evans: There are many forms of pollution, CO2 is not pollution. CO2 is beneficial to plants and doesn't seem to have a significant effect on the earth's temperature. I agree that the government should be regulating the earth's pollution but it's a different question that global warming.

Christopher asks: Dr Evens would you say that the amount of CO 2 released into our atmosphere every day has no effect on the world climate?

Dr David Evans: Almost no effect. There is no evidence that it has a significant effect. The case that most scientists consider is what happens if CO levels double from a pre industrial level of 280mmp to 580mmp, which we will get to in 2100AD. Theoretical estimates range from 1/4 degree to 6 degrees. The most creditable theoretical calculation was preformed by a Hungarian mathematician at NASA named Miskolczi. He took everything he could into account and updated the NASA calculation and his answer was 1/4 degree. NASA didn't like the answer and made him feel uncomfortable and he resigned shortly after. In any case, the best theory and the actual evidence suggest the influence of CO2 to the earth is small to negligible.

Buzzard asks: Based on your calculations, how much further will sea levels have risen, especially around Melbourne within the next 10 years?

BruceV asks: Is it true that if there were high levels of Co2 in there atmosphere the sky would be a red colour?

Dr David Evans: No, I don't think so. CO2 is colourless. In commercial greenhouses the CO2 level are pumped up quite high and it's still colourless.

Zeus asks: Has the decrease in temperature over the last 7 years or so corresponded with a decrease in sun spot activity?

Dr David Evans: The last 7 years has seen a period of flat temperatures with a small downward bias. It's too early to say temperatures are dropping even in the last year they have dropped a little. We're looking here for temperature trends which typically exhibit themselves over 5 years or so, so I think it's safer to say that temperatures have levelled out since 2001. The correlation with solar activities are very interesting, bare in mind that they are only correlation and nothing has been proven. However the late appearance solar cycle 24, suggest the next 24 years or so might be a little cooler.

Hochie asks: Dr Evans, do you know of any alternative theory for the changing global average temperatures over the past millennium, or over past ages? E.g. I heard something about solar output fluctuating over time and I wondered if there is any data on that.

Dr David Evans: The sun affects the earth's temperature in two ways. Firstly, there can be changes in solar eradiation, meaning the amount of heat pumped out by the sun. People have observed slight variation over the decades. Secondly and probably more significantly, the sun effects cloud formation on earth through solar magnetic effects. High energy cosmic rays strike the earth and help create clouds. And those clouds had a cooling effect on the earth. But the sun's magnetic shields us from some of those high energy cosmic rays. So when the sun is active, the earth gets less high energy cosmic rays so there are fewer clouds and it gets warmer. The sun has been pretty active in the last few decades. This theory still hasn't been proven and is just at the stage of correlations. There are probably half a dozen likely influences on the global temperature and at this stage I don't know of any good evidence to know, which are the important ones except to say that because the signature is missing, we can pretty much rule out carbon emissions.

listener asks: Here is a question that concerns me in relation to the doom and gloom prediction. Given there is evidence that our earth has gone through this cycle over trillions of years, is it possible the observation is just that, observation, and there are no solutions?

Dr David Evans: Yes, it's quite possible that we humans have no effect on temperature. And all we're seeing is natural variation. Bear in mind that it was warmer in the medieval times 800 years ago and it was a couple of degrees cooler in the 17 hundreds when they had a mini ice age. Humanity generally flourish when it is hotter, so personally I regard a little bit of heating as a good thing.

Susie asks: Dr Evans, could you please explain what you believe to be the cause of global warming if it is not carbon emissions.

Dr David Evans: I don't know. Possible causes are solar magnetic effects (which influence cloud level and therefore the earth's temperature), ozone depletion, industrial pollution such as aerosols, changes in greenhouse gases and anything that influence the ozone layer including electromagnetic radiation. And there are quite a few others. At this stage we don't have enough evidence to know what is really causing it. However correlation with solar activities is pretty strong, so the answer probably involved the sun and the clouds.

Cid asks: Dr Evans would not enhancing electricity production be a more innovative path to thus take?

Dr David Evans: As an electrical engineer I think that electricity production is an exciting topics and I wish we had more diversity in the means of production. I encourage people to do research on solar and other renewables.

mainst asks: David....... Thank you for speaking out. The voices of reason have been swamped by Hansen, Gore & the IPCC et al recently. What are your thoughts on the current solar minimum & have you heard of any research being done on intergravitational waves and their potential effects on the forces that drive the core of our planet?

Dr David Evans: No I haven't heard anything about intergravitational waves, thank you for your kind comments. It's encouraging to see that journalists are finally paying attention to this fine issue.

observer asks: Dr Evens what are your thoughts on sun spots being the primary cause of global warming?

Dr David Evans: It's a good possibility, not proven but correlations right up till today are good. It's important to see that solar activity does not correlate with NASA GISS temperatures, because they come from land based thermometers and are corrupted by the urban land heat effects. However solar activities correlate very well with satellite temperatures right up to 2008.

true asks: I to have been wondering the truths or smoke and mirrors that governments often use to create taxes, but being a layperson and taught that our planet has had ice ages and warmed up many times what makes so different this time?

Dr David Evans: We don't know that it is any different this time. The alarmist want us to believe that our emission of CO are warming the planet and while that seems a reasonable proposition two decades ago, the evidence has changed in the last decade to indicate that is certainly not the case. We don't know what caused the recent global warming, but chances are the causes are natural.

KevinM asks: DR Evans, Thank you for being up front with this CO2 thing, We grow plants in elevated co2 atmospheres and when co2 increases the plants grow quicker which balance the co2 back to 280 ppm, this is what should happen in nature?

Dr David Evans: CO2 is good for plants. We humans have been digging CO2 out from under the desert in Saudi Arabia and efficiently distributing it across the planet. Plants need carbon to grow, in fact they need it more than water. Satellite data shows that over the last 2 decades the amount of plant biomass on the planet has increased by 6 percent. So increasing the CO2 levels is helping feed the planet. Not only is CO2 not pollution, but it is beneficial to all plants and most animals on the planet.

Bo asks: Dr Evens I believe that the planet has been and is always evolving with massive changes to the environment over many thousands of years. Why do we think as humans living for only a short time on this planet, that we can change things?

Dr David Evans: That's a philosophical and political question and I'd rather just stick to the Science questions, sorry.

seeking asks: if all things are considered is it true that any measures that we take now will not be strong enough to combat global warming.

Dr David Evans: Probably very little. We couldn't find the greenhouse signature in the last 2 decades and that tells us that increasing the amount of greenhouse gases is having very little effect on the global temperature. Even a big sustained release of methane probably won't affect the global temperature very much.

nwo asks: Dr Evens. Can you please give your opinion on studies that may suggest that the sun is actually getting hotter and attributing not only to global warming on earth but on other planets as well ?

Dr David Evans: I haven't seen any good evidence on this, but otherwise I don't know much about it.

ord asks: if all things are considered is it true that any measures that we take now will not be strong enough to combat global warming.

Dr David Evans: We don't know what causes global warming, except that we now are pretty sure that carbon emissions do not cause it. Therefore taking measures to decrease our carbon emissions won't have any significant effect.

pete asks: Dr Evans, our Prime Minister, who states that he, is no scientist, stated in the report that humans were to blame for increases in global temperature, which is wrong; as if we follow his point of view; we are only adding to a natural cycle, therefore we are not solely to blame (way to go Kevin). Do you get disheartened with peoples natural tendencies to follow what is being stated in popular press? Rather than looking at data which shows that the Earth’s temperature has differentiated over its’ biographic life, at periods being above modern temperatures.

Dr David Evans: Many of the crucial issues in global warming are pretty simple. Well within the grasp of any educated citizen such as the Prime Minister. You only need a high school education to be able to read a temperature graph, and to see that the temperatures have been flat since 2001. You only have to be vaguely aware of the debate to notice that the alarmist are offering no actually evidence, only results from computer models. These are things that any political or journalist should feel confident in doing. I urge our Prime Minister to spend a little more time investigating the issue himself instead of just relying on the advice of people's whose jobs depend on the belief that carbon emission cause global warming.

DJ asks: Dr Evans, do you believe that animals such as Polar Bears etc will really become extinct as a result of the climatic changes being experienced? What do you believe will really happen with regard to future Australian weather patterns - are we in for more severe droughts/cyclones, etc?

Dr David Evans: Australian weather patterns are dominated by the pacific decadal osolation (PDO), there are periods of about 40-50 years when El-Nino dominate and there are period of about 40 years or so when lanigo dominate. The result is that Australian's weather systems goes for about 40 years or so of drought, and then 40 years of so of floods. As far as I am aware, this pattern hasn't changed and will probably continue into the future. Satellite data since 1979 indicate that the Southern hemisphere has no existed any global warming, as it happens, global warming is a pheromone that only effects the Northern hemisphere. Global warming and weather are influence by clouds, rain and water vapour all these issues are very closely tired together. I don't think any one fully understands them yet.

mattJ asks: You mentioned that "it was warmer in medieval times", but do you accept the possibility that the medieval Warm Period may have been partly a regional phenomenon, with the extremes reflecting a redistribution of heat around the planet rather than a big overall rise in the average global temperature?

Dr David Evans: Temperature records for that period are of course very sketchy. However what evidence we do have via proxy and historical records, suggest it wasn't just Greenland that was warm, that it was spread around the planet. Exactly how much warmer is certainly open to dispute. So in summary, it is possible though unlikely.

Hunter asks: I am concerned about the environment like most people, but I believe that we should react to accurate information. I am just as concerned that how the world is reacting about global warming scares now is similar to how we all were told that the millennium bug would stop society.

Dr David Evans: Yes, it's important to get our response right. If the alarmist are correct, then we should cut down our carbon emissions of the planet with overheat. If the alarmist are wrong, it's important not to cut back our carbon emissions or we'll create wide spread poverty unnecessary. There is no real substitute, except the get the real science right.

x asks: Weather models are notoriously unreliable due to the chaotic effects present in weather systems. What degree of confidence do the computer models on CO2 hotspots provide?

Dr David Evans: The hotspot due to enhance greenhouse is a central feature of all models. If the hotspot is not there, then either carbon emissions don't cause global warming or we completely misunderstand the climate system. The hot spot is something we except for theoretical reasons, but it's very central to our understanding.

8.technical asks: OK let's say that CO2 is not a problem. But is there added greenhouse effect due to airborne pollutants or would you say that has been overstated as well? It's hard to get the 'straight dope' on these issues.

Dr David Evans: On that issue, no one I know of has the 'straight dope'. The problem of industrial emission is normally called aerosols. It's not clear at this stage if aerosols increase the temperature of maybe lower the temperature. But we do know they are having some significant effect. At the moment the IPCC think they probably increase temperature, and I'm inclined to believe them.

Interviewer: Dr Evans unfortunately we are out of time tonight, do you have any final words for those who have come to the interview?

Dr David Evans: Thanks for your attention, this issue will get sorted out because it’s an issue of science. No amount of human arguing and can affect the actual effects of global warming and it will be another 2-3 decades of research before we will probably have a definitive answer as to what causes global warming. Stay Tuned ... Dr Evan's website: www.sciencespeak.com

Interviewer: This concludes our chat with Dr David Evans, Sunday August 17, 2008.